diff --git a/Lib/threading.py b/Lib/threading.py
index d010b80..8661cde 100644
--- a/Lib/threading.py
+++ b/Lib/threading.py
@@ -391,6 +391,9 @@
     # shutdown and thus raises an exception about trying to perform some
     # operation on/with a NoneType
     __exc_info = _sys.exc_info
+    # Keep sys.exc_clear too to clear the exception just before
+    # allowing .join() to return.
+    #XXX __exc_clear = _sys.exc_clear
 
     def __init__(self, group=None, target=None, name=None,
                  args=(), kwargs=None, verbose=None):
@@ -527,6 +530,13 @@
             else:
                 if __debug__:
                     self._note("%s._bootstrap(): normal return", self)
+            finally:
+                # Prevent a race in
+                # test_threading.test_no_refcycle_through_target when
+                # the exception keeps the target alive past when we
+                # assert that it's dead.
+                #XXX self.__exc_clear()
+                pass
         finally:
             with _active_limbo_lock:
                 self._stop()